Method and apparatus for producing oil from multiple strata from single well bore



W. P. MASSEY METHOD AND APPARATUS FOR PRODUCING OIL FROM Nov. 5, 1963 3,109,376

MULTIPLE STRATA FROM SINGLE WELL BORE Filed Aug. 10, 1959 5 Sheets-Sheet l INVENTOR William P. Massey ATTORNEY Nov. 5, 1963 w. P. MASSEY 3,109,376

METHOD AND APPARATUS FOR PRODUCING oIL FROM MULTIPLE STRATA FROM SINGLE WELL BORE Filed Aug. 10, 1959 5 Sheets-Sheet 2 n-p1 L'EaL I I II-QJ Z8 Fig.3

| m n "-n I I I'll] L ll 1 INVENTOR O r I 20 William P Massey z? 26' Fig. 4 ATTOME'Y.

Nov. 5, 1963 w. P.

METHOD AND APPARATUS FOR PRODUCING on. FROM MASSEY MULTIPLE STRATA FROM SINGLE WELL BORE 3 Sheets-Sheet 3 Filed Aug. 10, 1959 \M N. La I Mb a 4 P I QN um M ATTORNEY United States Patent 3,1639 376 METHGD AND AllPARATEfJS FGR PR'ODUCENG til-L FiE UM MULTIPLE STRATA snow SENQLE BELL EQRE William P. Massey, R6. Box 13186, @dessa, Ten. Filed Aug. it 1959, Ser. No. 332,767 2 tClaims. (G. 103-4) This invention relates to a method and apparatus for producing oil from a plurality of subsurface producing formations or zones in a single borehole, and it has particular reference to the provision of apparatus by which two or more oil producing strata can be caused to yield petroleum in profitable commercial quantities while utilizing a single casing but through different flow tubes.

Another object of the invention resides in the provision of a simple means by which oil can be recovered through the intermittent operation of gas lift stationed at predetermined levels in a borehole and arranging pacner elements between the productive formations so as to separate the same according to their productiveness, affording means by which oil can be produced from any selected formation automatically at predetermined time intervals.

The producing zones of a multiple Well are not always gas lifted in the same manner, due to the fact that the different reservoirs may have different characteristics, such as the bottom hole pressure and the productivity index thereof.

A multiple well may be gas lifted by use of a combination of any two of three methods:

(1) Continuously, at a predetermined rate;

(2) Automatically, in response to pressure of well fluids; and

(3) intermittently, by pressure of gas introduced into well from extraneous source, in accordance with predetermined time cycle.

The intermittent process of gas lifting well fluids from a plurality of producing zones in a well has found Wide application because it is usable for almost all well conditions. it can be assumed that the intermittent process is most desirable for gas lifting zones under most conditions.

The principal objection to the intermittent type of multiple gas lift has been that the pressure controlled or intermittent valve strings in a well having a plurality of producim zones are incompa ible when using the casing annulus as a common source of gas. Since bottom hole pressure decline usually is inevitable, changing conditions can cause one string to have a lower injection or producing level than the other. This means thieving of most of the gas by one zone and high gas input ratios. The other of the zones are starved for gas and do not produce the required amount of fluid.

This invention contemplates an intermittent gas lift operation in which gas injection to the several producing zones of a single well is controlled by a time cycle controller which also controls diaphragm operable valves at the surface which regulate the flow of fluid from the respective producing zones. The diaphragm operable valves are normally open, allowing static build-up of each zone between injections.

According to the invention, the discharge of injected gas, along with Well fluids, from one of the producing zones of a dual well is positively discontinued, by operation of the corresponding diaphragm operable valve, during the time interval that fluids are being produced from the other producing zones.

Broadly, therefore, the invention contemplates the provision of a method by which oil can be produced from a plurality of different producing formations automatically in accordance with the characteristics of each formation,

3 E 6 Patented Nov. 5, 1%63 L 1 and apparatus which includes automatic time cycling control devices by which the gas lift valves can be operated at different stations in accordance with the predetermined production capabilities of the different formations irrespective of their sequence in subterranean levels.

While the foregoing objects are paramount, other and lesser objects will become manifest as the description proceeds, taken in connection with the appended drawings wherein:

FIGURE 1 is a diagrammatic elevational view showing a well bore traversing a plurality of producing formations, and showing apparatus embodying the invention operatively associated therewith;

FEGURE 2 is a. perspective view showing the time cycle controlling mechanism, with the front cover partly broken away to show the adjacent side thereof, and showing the pressure regulators;

FEGURE 3 is an elevational view taken at right angles to the view shown in FIGURE 2, illustrating the time cycle controlling mechanism in association With the diaphragm operable vmve controlling the injection of gas in the well;

FIGURE 4 is an elevational view showing the time cycle controller with the rear cover removed to show the adjacent side thereof, and illustrating the pressure regulators and a portion of the diaphragm operable valve controlling the injection of gas in the well; and

FIGURE 5 is a flow diagram showing the operation of the time cycle controller whereby it controls the supply of gas pressure to the diaphragm operable valves regulating the injection of gas into the well and the flow of fluids from the several producing zones thereof.

The arrangement shown in FIGURE 1 is merely illustrative of the application of the method and apparatus herein described and is in no way intended to limit the invention in its adaptation for use in any desired number of different producing formations which can be produced from a single well.

Referring now to FEGURE 1 of the drawing, the numeral l designates a Well bore, which traverses a plurality of producing formations, indicated by the numerals 2 and 3. A well casing, indicated by the numeral 4, has a casing head 5 and is perforated at 6 and 7, at the respective producing formations 2 and 3.

A plurality of flow tubes, 8 and 9, which are connected at the surface to flow lines 10 and 11, extend downwardly into the well bore 1 and terminate at their lower ends at the producing formations 2 and 3.

The portions of the how tubes 8 and 9 below the surface are designated by the numerals l2 and 13 and each has a plurality of pressure controlled or intermittent type gas lift valves 1'4 connected therein at predetermined spacings and a check valve 14 in its lowermost end. The lower ends of the portions 12 and 13 of the flow tubes 8 and 9 extend into the different producing formations and those extending below the upper producing stratum have tail pipes or snorkel tubes 15 therein.

As illustrated in FIGURE 1 the different producing formations are separated from the upper casing chamber and each other by packers 16 and 17, the former providing a pressure area in the upper portion of the easing into which gas under pressure is intermittently introduced at the surface through a supply line 13. The producing areas below the packer 16 are separated as by the packer 17, the several flow tubes being extended through the packers l6 and 17 into the different areas so that oil can be produced therefrom individually through the check valves 14' and the tail pipes or snorkel tubes 15 in any sequence best suited to the character of each formation.

The gas supply line 18 has a valve 19 therein automatically operable by a diaphragm 20 in response to the action of a time cycle control mechanism 21, as hereinv.9 after described, whereby gas is introduced into the casing 4 intermittently in accordance with a predetermined time cycle. Gas pressures introduced to the producing formations are controlled by the valves 14 connected into the members 12 and 13 and these valves are adjusted to operate at'different pressures, according to the lift involved, and at predetermined time cycles. The gas enters the members 12 and 13 through the valves 14 and is conducted downwardly through the flow tubes around the tail pipes 15 to raise the column of oil which has flowed into the lower ends of'the tubes through the check valves 14' by formation pressures. The injected gas, of course, follows the well fluid to the surface.

Each of the flow tubes 8 or 9, and whose portions 12 or 13 extend below the upper packer member 16, has a fitting 15 in its lowermost end whereby to support a tail pipe 15, such as illustrated in FIGURE .1, in a manner enabling it to be installed from the surface and removed if desirable to do so. It is obviously necessary to conduct the injected gas to the lower producing zones through the flow tubes around the tail pipes being closed to the upper zones which they traverse.

As shown in FIGURE l, the tail pipe 15 is removably supported on the fitting 15' within the flow tube 13 and extends downwardly therein from a point above the packer 16, and above the lowermost gas lift valve 14, to a point immediately above the check valve 14.

The tail pipe 15 has an externally enlarged upper end, having a diameter corresponding substantially to the inside diameter'of the flow tube 13, whereby the annulus between the tail pipe 15 and the flow tube 13 is closed.

The tail pipe 15 provides a fluid passage, in the annulus between the tail pipe 15 and the flow tube .13, communicating at its ends with the lowermost gas lift valve 14 v and with the interior of the flow tube 13 above the check to the action of the time cycle controller 21, whereby the discharge of injected rgas, along with well fluids, from one of the producing zones is positively discontinued during the time interval that fluids are being produced from one of the other producing zones. The time cycle controller 21 is supplied with gas under pressure from the gas supply line 18 through a bypass line 26 having pressure regulators 27 and 28 therein.

As shown in FIGURES 2 to 5, the operating pressure is communicated to a manifold 29 having two pairs of three way values, numbered 3%, 31, 32 and 33, in gas communication therewith. The operating pressure is also communicated, through :a relay valve 34, to the diaphragm 2!} of the valve 19, which controls the supply of gas to the casing 4, whereby the valve U is normally closed. The relay valve 34 is operable by a diaphragm 35, and in one position thereof is adapted to bleed off pressure from the diaphragm 2d of the valve 19.

The time cycle controller includes a clock actuated cam wheel 36 having cam surfaces acting on cam followers 37 carried by weight bars 38, one of which corresponds to each of the three way valves 30, 31, 32 and 33, and which are pivotally supported at one end and normally have their free ends resting on the three way valves, whereby the weight bars 38 are lifted and the three way valves 30, 31, 32 and 33 are opened, one pair at a time.

In their open positions, the three way valves 34 and 33 are in gas communication with the diaphragms 24 and 25 of the valves 22 and 23, which control the discharge of injected gas and well fluids through the flow lines it and 11, respectively, while the three way valves 31 and 32 are in gas communication with the diaphragm 35 of the'relay valve 34.

The arrangement is such that the relay valve 34 is T5, the flow tubes from the upper producing zone 2. The process is re peated automatically at predetermined time intervals.

The valve 22 remains closed for a longer period of time than the gas injection period, whereby gas is supplied to the casing 4 to lift the lower producing zone 3 only. The valve 22 opens after the fluid slug from the lower producing zone 3 reaches the surface. The next gas injection period closes the valve 23, and the upper producing zone 2 is produced in the same manner.

The structure herein described and the arrangement thereof is obviously capable of substantial changes and modifications by persons skilled in the art without departing from the spirit and intent of the invention or the scope of the appended claims.

What is claimed is:

1. Apparatus for producing oil from a well having a plurality of producing zones at different elevations, whereby oil is produced successively and intermittently from the respective producing zones according to a predetermined time cycle, by gas lift, comprising, in combination, a casing operatively positioned in a well and having perforations therein opposite the producing zones, thecasing being closed at the surface, a first packer in the casing above the uppermost producing zone defining a fluid chamber above the first packer, a second packer in the I casing below the first packer and above a lower producing zone defining, with the first packer, fluid chambers above and below the second packer, a gas supply pipe communicating with the casing at the surface, above the first packer, a first flow pipe in the casing traversing the fiuid chamber above the first packer and extending downwardly below the first packer, the first flow pipe having a check valve in its lower end, below the first packer, and having gas lift valves operatively connected thereto above the first packer, a second flow pipe in the casing traversing the fluid chambers above and below the first packer and extending downwardly below the second packer, the second fiow pipe having a check valve in its lower end, below the second packer, and having gas lift valves operatively connected thereto above the first packer, a tube of smaller diameter having means removably supporting it within the second flow pipe and extending downwardly therein from a point above the first packer, and above one of the gas lift valves, to a point immediately above the check valve, the tube having an externally enlarged upper end, having a diameter corresponding substantially to the inside diameter of the flow pipe and coacting with said supporting means to close the annulus between the tube and the flow pipe at the upper end of said annulus, and the tube providing a fluid passage in the annulus between the tube and the flow pipe communicating at its ends with the last mentioned gas lift valve and with the interior of the flow pipe above the check valve, whereby fluid entering the second flow pipe through its check valve is forced downwardly therein and upwardly through the tube, a diaphragm operable valve in the gas supply pipe, a diaphragm operable valve in each of the first and second flow pipes, at the surface, and automatic time cycle control means acting on the first mentioned diaphragm operable valve to open it at predetermined time intervals, whereby 'gas is introduced into the well casing, and acting on the last mentioned diaphragm operable valves to selectively close them, to positively prevent the discharge of injected gas and well fluids from one of the zones, at predetermined time intervals coinciding with the opening of the first mentioned diaphragm operable valve.

2. The structure of claim 1, the automatic time cycle control means comprising a gas bypass line communicating with the gas supply pipe upstream relative to the first mentioned diaphragm operable valve, a relay valve oper-atively connected in the gas bypass line and controlling the supply of gas to the first mentioned diaphragm operable valve whereby it is actuated, the relay valve having means for bleeding off gas pressure from the diaphragm controlling the first mentioned diaphragm operable valve, to thereby open the valve, a first pair of cam operable valves, controlled by a timing mechanism, operatively connected in a manifold communicating with the gas bypass line through a branch pipe and controlling the supply of gas to the relay valve whereby it is actuated, so that the first mentioned diaphragm operable valve is adapted to be opened intermittently in accordance with a predetermined time cycle, and a second pair of cam operable valves, controlled by the timing mechanism and operable in unison with the cam operable valves of the first pair, respectively, operatively connected in the manifold and controlling the supply of gas to the last mentioned diaphragm operable valves whereby they are actuated, so that the last mentioned diaphragm operable valves are adapted to be closed selectively, in accordance with a predetermined time cycle, simultaneously with the opening of the first mentioned diaphragm operable valve.

References Cited in the file of this patent -UNITED STATES PATENTS 2,208,036 Kymer July 16, 1940 2,213,372 Aucoin Sept. 3, 1940 2,339,487 King Jan. 18, 1944 2,680,408 Davis June 8, 1954 2,876,703 Carlisle Mar. 10, 1959 2,896,547 Franey, et a1. July 28, 1959 2,917,004 Davis Dec. 15, 1959 2,963,089 Siger Dec. 6, 1960 

1. APPARATUS FOR PRODUCING OIL FROM A WELL HAVING A PLURALITY OF PRODUCING ZONES AT DIFFERENT ELEVATIONS, WHEREBY OIL IS PRODUCED SUCCESSIVLY AND INTERMITTENTLY FROM THE RESPECTIVE PRODUCING ZONES ACCORDING TO A PREDETERMINED TIME CYCLE, BY GAS LIFT, COMPRISING IN COMBINATION, A CASING OPERATIVELY POSITIONED IN A WELL AND HAVING PERFORATIONS THEREIN OPPOSITE THE PRODUCING ZONES, THE CASING BEING CLOSED AT THE SURFACE, A FIRST PACKER IN THE CASING ABOVE THE UPPERMOST PRODUCING ZONE DEFINING A FLUID CHAMBER ABOVE THE FIRST PACKER, A SECOND PACKER IN THE CASING BELOW THE FIRST PACKER AND ABOVE A LOWER PRODUCING ZONE DEFINING, WITH THE FIRST PACKER, FLUID CHAMBERS ABOVE AND BELOW THE SECOND PACKER, A GAS SUPPLY PIPE COMMUNICATING WITH THE CASING AT THE SURFACE, ABOVE THE FIRST PACKER, A FIRST FLOW PIPE IN THE CASING TRANVERSING THE FLUID CHAMBER ABOVE THE FIRST PACKER AND EXTENDING DOWNWARDLY BELOW THE FIRST PACKER, THE FIRST FLOW PIPE HAVING A CHECK VALVE IN ITS LOWER END, BELOW THE FIRST PACKER, AND HAVING GAS LIFT VALUES OPERATIVELY CONNECTED THERETO ABOVE THE FIRST PACKER, A SECOND FLOW PIPE IN THE CASING TRANSVERSING THE FLUID CHAMBERS ABOVE AND BELOW THE FIRST PACKER AND EXTENDING DOWNARDLY BELOW THE SECOND PACKER, THE SECOND FLOW PIPE HAVING A CHECK VALVE IN ITS LOWER END, BELOW THE SECOND PACKER AND HAVING GAS LIFT VALVES OPERATIVELY CONNECTED THERETO ABOVE THE FIRST PACKER, A TUBE OF SMALLER DIAMETER HAVING MEANS REMOVABLY SUPPORTING 